Suppose a builder pitches a 100-condominium development in Richmond within 1,000 feet of Interstate 80.

Under proposed air-quality guidelines, for the first time in the U.S., if extra cancer risk meets a specific threshold, the developer would be told to study the potential health effects of the freeway pollution on the people who would live in the homes. That would be in addition to what the developer is already required to do: study the effects of the housing on freeway traffic and the surrounding environment.

If the health risk is too great, the developer might need to modify or scrap his development plan, or spend extra time persuading the city or county to approve it.

This proposal to more closely scrutinize how people in new housing would be affected by existing pollution sources — rather than be satisfied just with studying how new freeways or other pollution sources affect existing neighbors — has thrust the Bay Area Air Quality Management District into another heated debate over pollution reduction.

Air district officials say their proposed guidelines for cities and counties to use in development reviews would break new ground in protecting the public from the risks of cancer, asthma, lung disease and other ailments caused or aggravated by toxic air pollution.

“This plan is about protecting public health by providing better air,” said Mark Ross, a regional air board member on the Martinez City Council. “This air district once again is in the vanguard of providing clean air.”

Builders contend the air district proposal is overzealous, would kick the struggling building industry when it’s down and stifle green development in Oakland, San Jose, Richmond and other cities that yearn for housing near transit centers and downtowns.

“You have cities and transportation agencies spending millions to bring about transit-oriented development, yet the air district is throwing up a new barrier. This makes no sense,” said Paul Campos, an attorney for the Homebuilders Association of Northern California. “This proposal would mean additional costs, uncertain delays, onerous regulation and expensive litigation for development.”

Environmentalists have had little to say about how the proposed guidelines would affect housing applications near pollution sources. They’re concentrating on trying to change another part of the proposal that would set up stricter review standards for the development of new pollution sources, such as gas stations, auto body shops or trucking centers, in six heavily polluted sections of the Bay Area.

The 22-member air board may vote Wednesday on the proposal.

Campos said the air district’s toxic pollution proposal could have reaching implications on plans to build housing, businesses, or other developments near pollution sources, as well as proposed new gas stations, power plants or other projects that emit pollution.

Air district managers said they made their proposal to steer cities and counties through the complicated, state-mandated reviews of pollution impacts from new development, and ways to reduce human exposure to the contaminants.

Cities and counties would retain their authority to decide whether and how development would occur. But the proposal would force them to scrutinize air quality more closely.

For the first time, the air district proposes to set a specific health-effects threshold, triggering studies to be done on pollution impacts and ways to reduce them.

Under the guidelines, cities and counties would require the studies when people to live in the proposed housing would be exposed to an extra risk of 10 in a million from a pollution source within 1000 feet.

Experts would arrive at the risk by studying the types, potency and amounts of pollution, and the distance to the nearest homes.

The air district already has a guideline calling for industrial developers to examine pollution effects on existing residents. Under the proposal, housing developers would have to do the same thing.

In the proposal, the air district for the first time would add diesel soot and fine particles as criteria for triggering a pollution study.

Cities and counties would be able to ignore the guidelines, but they would risk being sued by project opponents alleging a violation of the California Environmental Quality Act.

Air district managers said having to do a pollution study wouldn’t doom a housing or business development plan, but could spur developers to take extra measures to reduce people’s exposure to the contaminants.

For example, a builder proposing homes near a freeway or industry could look into ways to locate the buildings and children’s outdoor play areas at the far end of the property to provide space for soot or fumes to disperse, said Gregory Tholen, an air district environmental planner.

The air district also proposes giving builders an alternative means to meet their obligation to consider pollution impacts.

Builders would not be required to conduct a detailed pollution study if their project is in a city or area that prepared a communitywide risk reduction plan with long-term measures to reduce toxic air emissions. The communitywide plans are also part of the air district’s proposal.

“We think a communitywide approach is the best way to reduce pollution rather than by a project by project approach,” said Henry Hilken, the air district’s manager of planning and research.

He suggested the community plans — first of their kind in the nation — might look at measures such as putting pollution filters on diesel trucks in local businesses, routing diesel trucks to stay away out of neighborhoods, or switching city vehicle fleets to use cleaner fuels.

That’s not good enough, said Campos of the builders association. It could take years and big bucks to prepare the community risk reduction plans, and building projects could lost their financing and die in the mean time, Campos said.

As builders attack the proposal as onerous, an environmental coalition has attacked part of the plan as too weak.

The Bay Area Environmental Health Collaborative contends the district should set a second and stricter cancer risk guideline for reviewing proposed new pollution sources if they are proposed in six areas with elevated concentrations of diesel soot and other toxic air pollution. An air district analysis has defined the areas as parts of Concord, Richmond, San Jose, Oakland, East Palo Alto and eastern San Francisco.

“These heavily impacted areas have already shouldered more than their share of toxic pollution,” said Gordon Mar, the health collaborative’s interim director. “There should be no new sources of toxic pollution in these areas.”

But air district managers and industries object, saying that setting stricter development guidelines in more polluted areas would discourage development and job creation there.

“We should be helping these urban areas that need economic development, not discouraging it,” said Dennis Bolt, a spokesman for the Western States Petroleum Association. “It’s the wrong way to go.”

Bolt also said that the environmental coalition’s proposal would make it harder to win permission for upgrades or modernizations of industrial plants, fuel pipelines or gas stations in the six areas with elevated pollution levels.

Denis Cuff covers environmental, water, and outdoor recreation news for the Bay Area News Group. A graduate of Stanford University with a B.A. in communications, he enjoys hiking and cycling in his spare time.

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